CVE-2026-28692: 
C# vulnerability analysis and mitigation

CVE-2026-28692 is a heap buffer over-read vulnerability in ImageMagick's MAT decoder, caused by incorrect parenthesization that forces 32-bit arithmetic instead of the appropriate bit width. It affects ImageMagick versions prior to 7.1.2-16 (7.x branch) and prior to 6.9.13-41 (6.x branch), as well as Magick.NET NuGet packages prior to version 14.10.4. The vulnerability was published on March 9, 2026, and has a CVSS v3.1 base score of 4.8 (Moderate) (GitHub Advisory, Red Hat).

The root cause is an integer overflow or wraparound (CWE-190) due to incorrect parenthesization in the MAT decoder, which causes 32-bit arithmetic to be used where wider arithmetic is required, ultimately resulting in an out-of-bounds read (CWE-125). A remote attacker can exploit this by supplying a specially crafted MAT image file to an application that processes images with ImageMagick; no authentication or user interaction is required, though the attack complexity is rated High. AddressSanitizer output confirms a heap-buffer-overflow with a READ of size 8 at an out-of-bounds address, as demonstrated in the advisory's proof-of-concept crash report (GitHub Advisory, Red Hat Bugzilla).

Successful exploitation can lead to disclosure of sensitive information from heap memory — potentially including credentials or other confidential data — and a denial of service (DoS) condition due to the abnormal read operation. The vulnerability primarily affects systems that process untrusted image files, such as automated image processing pipelines or web applications accepting user-uploaded images. Integrity is not impacted, and there is no evidence of lateral movement potential beyond the affected process (GitHub Advisory, Red Hat).

1. Reconnaissance: Identify target applications or services that accept image file uploads or process images using ImageMagick versions prior to 7.1.2-16 or 6.9.13-41, particularly those that support MAT (MATLAB) format processing.
2. Craft malicious MAT file: Create a specially crafted MAT image file designed to trigger the 32-bit integer overflow in the MAT decoder, causing the decoder to calculate an incorrect buffer size or offset.
3. Submit the file: Upload or supply the malicious MAT file to the target application (e.g., via a web form, API endpoint, or automated pipeline that invokes ImageMagick for image processing).
4. Trigger heap over-read: When ImageMagick processes the file, the incorrect parenthesization causes 32-bit arithmetic to be used, resulting in a heap buffer over-read — reading up to 8 bytes beyond the allocated buffer boundary.
5. Achieve objective: Depending on heap layout, the attacker may obtain sensitive data leaked from adjacent heap memory (information disclosure) or cause the ImageMagick process to crash (DoS) (GitHub Advisory).

• Logs: Application or web server logs showing repeated submission of .mat files or MAT-format image data to image processing endpoints; ImageMagick error logs or crash reports referencing heap-buffer-overflow or AddressSanitizer output.
• Process: Unexpected crashes or abnormal termination of ImageMagick worker processes (convert, magick) when processing MAT files; core dump files generated by the ImageMagick process.
• File System: Presence of unusual or malformed .mat files in upload directories or temporary image processing folders.
• Network: Repeated or automated submissions of MAT-format image files from a single source IP to image upload or processing endpoints.

Update ImageMagick to version 7.1.2-16 or later (7.x branch) or 6.9.13-41 or later (6.x branch); Magick.NET users should upgrade to version 14.10.4 or later. As a workaround, disable or restrict MAT format processing in ImageMagick's policy.xml if MAT support is not required by the application. Additionally, running ImageMagick in a sandboxed or containerized environment and implementing strict input validation on accepted image file types can reduce exposure (GitHub Advisory, Red Hat Bugzilla).

The vulnerability was reported by security researcher ylwango613 and published by ImageMagick maintainer dlemstra on March 9, 2026. Downstream Linux distributions including Debian, SUSE/openSUSE, and Amazon Linux 2 have issued security advisories and updated packages. Detection plugins have been published by Tenable (Nessus) and Qualys, indicating broad scanner coverage. No significant social media controversy or high-profile researcher commentary beyond standard disclosure has been observed (GitHub Advisory, Red Hat).